This invention relates to a window regulator assembly, and more particularly, the invention relates to a drum for taking up the slack in a drum and cable window regulator assembly.
Window regulator assemblies are used to raise and lower a window in a vehicle door. One type of window regulator assembly utilizes a drum driven by an actuator and a pair of cables connected to the drum. The cables are connected to a member supporting the window, which is mounted on a guide. The actuator rotates the drum and raises and lowers the member along the guide. To ensure desired operation of the window regulator, the cables should maintain a constant length.
Over the life of the window regulator assembly, the cables stretch undesirably. As a result, the window may not be raised or lowered in a desirable manner and may bind or make noise. Some tensioning devices have been proposed to take up the slack in the cables. The proposed tensioning devices may be rather complicated, or may not operate in a manner as desired. Therefore, what is needed is an improved and simplified window regulator tensioning device for a drum and cable assembly.
The present invention provides a window regulator assembly including a guide defining a path. A window bar assembly having a window mounted thereon is supported on the guide and is movable along the path. A manual or automatic actuator is interconnected with a drum for rotationally driving the drum. A pair of cables each include an end connected to the drum with the opposing end connected to the guide. The cables are arranged in a pull-pull relationship between the drum and guide. A portion of the cables is wrapped about the circumference of the drum. A drum biasing assembly, which may include a mandrel urged into bore of the drum by a spring, expands the circumference of the drum to take up the slack in the cables. The drum includes radial grooves that divides the drum into sectors that are movable relative to one another by the mandrel.
Accordingly, the above invention provides an improved and simplified window regulator tensioning device for a drum and cable assembly.